Revealing mistake: When a force 10 gale is blowing and the CGI snow is horizontal... ... none of the trees move one bit, not one.
Visible crew/equipment: As Captain Henry rides off towards the end, there is a propane burner/heater on the ground to the left between the pine trees that he rides right past. (02:08:35)
Continuity mistake: When Glass goes into the river to escape from the chasers, there is a bandage on his head. He loses it after the waterfall, then somehow the bandage comes back. When he manages to grab some wood to save himself, the bandage has gone again.
Continuity mistake: When he falls into water there is no snow around the river, but 10 seconds later there is some.
Deliberate mistake: At about 1:49 in the movie, Glass is awakened by an attacking force of Arikara, and he fires his single-shot, muzzle-loading flintlock pistol at the nearest one coming at him. Then he runs to his nearby horse and flees, turning back to fire the gun a second time immediately. No reloading and no second gun on his person. It never leaves his hand; he's whacking the horse's rump with it to goad it on as soon as he jumps on it. And then he fires that same gun another time in a matter of seconds. (01:40:00)
Chosen answer: They stumble over a burnt Indian camp and found the two horses there.
Julian1990